Water cooled electrode head for electric furnace electrodes or the like



Aug. 1, 1967 A. H. TURNER WATER COOLED ELECTRODE HEAD FOR ELECTRICFURNACE ELECTRODES OR THE LIKE 3 Sheets-Sheet 1 Filed April 23, 1964lzvvnvroe AL FRED H. Tun/v52 4rr'r$.

JAM/AM WATER COOLED ELECTRODE HEAD FOR ELECTRIC Aug. 1, 1967 A H. TURNER3,334,170

FURNACE ELECTRODES OR THE LIKE Filed April 23, 1964 5 Sheets-Sheet 2 iii/NVEAITOR V5 \O 41.1mm H. TURNER L lj Aug. 1, 1967 A. H. TURNER WATERCOOLED ELECTRODE HEAD FOR ELECTRIC FURNACE ELECTRODES OR THE LIKE 3Sheets-Sheet :5

Filed April 23, 1964 R M TR r a. V 1 3 A n a Arrars.

United States Patent WATER COOLED ELECTRODE HEAD FOR ELECTRIC FURNACEELECTRODES OR THE LIKE Alfred H. Turner, Pinson, Ala. (P.O. Box 1148,Birmingham, Ala. 35201) Filed Apr. 23, 1964, Ser. No. 361,991 Claims.(Cl. 13-16) This invention relates to new and improved electrode headsfor use with electric furnace electrodes or the like. In variousaspects, the present invention may be regarded as an improvement uponthe invention disclosed and claimed in the prior patent of the presentapplicant, No. 2,997,511, issued Aug. 11, 1961.

One object of the present invention is to provide a new and improvedelectrode head having contact shoes which are adapted to engage theelectrode, the contact shoes being readily removable and replaceable sothat new contact shoes may be quickly and easily installed if the oldshoes become damaged or worn.

A further object is to provide such a new and improved electrode head inwhich the contact shoes are formed with internal passages for thecirculation of cooling water.

Another object is to provide such a new and improved electrode head inwhich the cooling water is supplied to the contact shoes by tubes orpipes which also carry the electrical current to the shoes.

A further object is to provide such a new and improved electrode headwhich is arranged so that the contact shoes may readily be disconnectedfrom the cooling water tubes.

Another object is to provide a new and improved electrode head of theforegoing character in which the contact shoes are preferably fabricatedfrom castings and plates which are made of copper and are weldedtogether,

so as to form the cooling water passages within the shoes.

It is another object to provide such a new and improved electrode headin which the base or body of the head is also formed with internalpassages for the circulation of cooling water.

A further object is to provide such a new and improved electrode head inwhich the contact shoes are preferably supported by curved bands whichare secured to the body and are adapted to embrace the shoes.

Still another object is to provide such a new and improved electrodehead which is highly economical, both as to original cost and the costof maintenance, and which minimizes the time required for maintenance sothat maintenance may be accomplished with a minimum loss of operatingtime.

Further objects and advantages of the present invention will appear fromthe following description taken with the accompanying drawings, inwhich:

FIG. 1 is a general plan view of an electrode head to be described as anillustrative embodiment of the present invention.

FIG. 2 is a side elevational view of the electrode head.

FIG. 3 is a fragmentary sectional view taken generally along the line3--3 in FIG. 2.

FIG. 4 is a fragmentary enlarged horizontal section taken generallyalong the line 44 in FIG. 2.

FIG. 5 is an enlarged plan view with one of the contact shoes and aportion of the body of the head broken away and shown in horizontalsection.

FIG. 6 is an enlarged side elevational view with portions of the headbroken away and shown in vertical section.

FIG. 7 is a plan view of one of the contact shoes.

FIG. 8 is an elevational view showing the radially inward side of one ofthe shoes with portions broken away and shown in section.

ice

FIG. 9 is an elevationalview looking edgewise at one of the shoes.

FIG. 10 is a fragmentary somewhat diagrammatic sectional view takengenerally along the line 10'--10 in FIG. 6.

As already indicated, the drawings illustrate an electrode head 20 foruse with a cylindrical electrode 22 of an electric furnace or the like.It will be understood that an electric furnace employs a plurality ofelectrodes, and that each electrode is provided with a separateelectrode head. The purpose of the electrode head 20 is to supplyelectrical current to the electrode 22 and also to provide at least someof the support for the electrode. Normally, the electrode 22 is made ofcarbon, either with or without a cylindrical sheath of metal. Typically,the electrode 22 and the electrode head are quite large. Thus, theparticular electrode head 20 which is illustrated in the drawings isintended for use with an electrode having a diameter of 24 inches. Muchlarger electrodes and electrode heads are also frequently employed. Itwill be evident that the weight of such electrodes is quite great, andthat the operating electrical currents for such large electrodes arevery high.

The illustrated electrode head 20 comprises a body or mounting portion24 which may be supported in the same manner as prior electrode heads.As shown, the body 24 is mounted on the outer end of a supporting arm26.

The illustrated body 24 comprises a vertical backplate 28 and a pair ofside members 30 which project from the opposite ends of the plate 28.The body 24 is adapted to be positioned opposite one side portion of thecylindrical electrode 22. v

The body 24 has upper and lower walls or plates 32 and 34 (FIG. 6) whichextend between the side members 30 and are welded or otherwise securedto the backplate 28. The upper and lower walls 32 and 34 also close theupper and lower ends of the side members 30.

As shown in FIGS. 1 and 2, the illustrated electrode 22 is provided witha pair of curved bands 36 and 38 which extend between the side members30 of the body 24 and are adapted to extend around the electrode 22. Theopposite ends of the bands 36 and 38 are welded or otherwise secured tothe side members 30. The welds are clearly shown at 40 and 42 in FIG. 2.

The illustrated electrode head 20 is provided with two contact shoes 44which are supported by the bands 36 and 38 and are adapted to be pressedagainst the electrode 22. The shoes 44 serve the purpose of carrying theelectrical current to the electrode 22. As shown in FIG. 1, a curvedclamp 46 is provided to develop clamping pressure between the electrode22 and the contact shoes 44. The clamp 46 is located between the sidemembers 30 and the body 24 and is positioned opposite the contact shoes44. As shown, the clamp 46 is mounted on the outer end of an operatingplunger or shaft 48 which extends through a large central opening 50' inthe backplate 28. The plunger 48 may be connected to a hydrauliccylinder or other similar device, not shown, which operates the clamp 46and is adapted to move the clamp into and out of clamping engagementwith the electrode 22. The plunger 48 extends along the length of thesupporting arm 26 and is movable longitudinally relative thereto.

Two tubes or pipes 50 and 52 are connected to each of the contact shoes44 and are adapted to carry the electrical current to and from theshoes. In addition, the tubes 50 and 52 carry cooling water which isci-rculated through the shoes to keep the shoes cool enoughv to avoiddamage to the shoes due to excessive heat. It will be understood thatthe shoes 44 are heated by the electrical current which passes betweenthe shoes and the electrode. Moreover, the electrode transmits heat fromthe electric furnace to the shoes. As shown, the tubes 50 and 52 areconnected to a clamp 54 which in turn is connected to a pair ofelectrical bus bars 56. The tubes 50 and 52, the clamp 54 and the busbars 56 should be made of a material such as copper, which is highlyconductive to electricity. Water pipes or hoses, not shown, may beconnected to tapped openings 58 and 60 in the ends of the tubes 50 and52.

Cooling water is also circulated through the body 24 of the electrodehead 20. The side members 30 of the body 24 are hollow to provide forthe circulation of the cooling water. As clearly shown in FIG. 10, apipe or tube 62 is connected between the two side members 30 to conductthe cooling water therebetween.

It will be seen from FIG. that each of the side members has an outerwall 64 and an inner wall 66 which are spaced apart to form a passage orchamber 68 through which the water is circulated. The walls 64 and 66extend between the upper and lower walls 32 and 34 and are welded orotherwise secured thereto. The backplate 28 closes the rear end of eachchamber 68, while the front end is closed by a wall 70, as will beclearly evident from FIG. 5.

Each side member 30 is provided with an upper port 72 which is formed inthe upper wall 32. A pipe or tube 74 may be connected to the port 72 tocarry the cooling water. Each side member 30 also has a lower port 76 towhich the interconnecting cross-pipe 62 is connected. The port 76 isformed in the lower portion of the inner wall 66.

In order to increase the cooling effect of the water, each chamber 68may be provided with a plurality of horizontal partitions 78, 79 and 80which are arranged to force the water to follow a serpentine path inpassing between the ports 72 and 76. Thus, as shown in FIG. 6, thepartitions 78 and 80 extend to the left from the backplate 28 so thatthe water is forced to pass through openings 82 and 84 between the endwall 70 and the left-hand ends of the partitions 78 and 80. On the otherhand, the intermediate partition 79 extends to the right from the endwall 70 so that the water is forced to pass through an opening 83between the backplate 28 and the righthand end of the partition 79.

The cooling water is caused to flow into the body 24 of the electrodehead 20 through one of the connecting pipes 74, while the water flowsout of the body 24 through the other pipe 74.

As already indicated, cooling water is circulated through each of thecontact shoes 44. To provide the necessary water passages, each shoe 44is preferably constructed in accordance with the invention disclosed andclaimed in the :applicants prior patent, No. 2,997,511, patented Aug.22, 1961. Thus, each of the illustrated shoes 44, comprises a curvedmember 86, preferably a casting, to which a curved plate 88 is welded.The plate 88 forms the inner wall of the shoe 44 and has a cylindricallycurved surface 90 which engages the outside of the electrode 22. Theplate 88 may be a cast member but it usually is formed of rolled metal.Both the casting 86 and the plate 88 should be made of a material suchas copper which is highly conductive to both electricity and heat.

The casting 86 is formed with a channel or cavity 92 which is closed bythe plate 88 to form the passage or chamber through which the coolingwater is circulated. To improve the effectiveness of the cooling water,a rib or partition 94 is formed on the casting 86 so as to bring about apartial subdivision of the cavity 92, so that the water has to flowalong a curved path of considerable length in passing through thecontact shoe. As clearly shown in FIG. 8, the partition 94 extendsdownwardly into the cavity 92 so as to force the water to pass through arestricted opening 96 between the lower end of the partition 94 and thelower end of the cavity 92.

The plate 88 covers most of the inside of the contact shoe 44, as willbe apparent from FIG. 8, but the shoe has an upper portion 98 whichextends above the plate and is flush with the exposed surface of theplate. The upper portion is formed with two ports 100 and 102 whichcommunicate with the upper end of the cavity 92 on opposite sides of thepartition 94. The illustrated ports 100 and 102 are downwardly tapered,for receiving the correspondingly tapered end portions 104 and 106 ofthe tubes 50 and 52. Rather than being threaded or screwed into theports 100 and 102, the tapered portions 104 and 106 of the tubes areclamped into the ports so as to facilitate the connection anddisconnection of the tubes from the contact shoes. Thus, each of thetubes 50 and 52 is provided with a clamping plate 108 which engages anenlargement or shoulder 110 which is formed on the tube just above thetapered end portion. The plate 108 is formed with an opening 112 throughwhich the tube extends. A plurality of bolts or screws 114 are employedto draw the plate 108 downwardly toward the contact shoe 44 so that theplate will clamp the tapered end portion of the tube into thecorresponding port. Tapped openings 116 are provided in the shoe 44 toreceive the threaded lower ends of the bolts 114.

Cooling water may be supplied under pressure by the tube 50 and may passthrough the port 100 into the cavity 92. The water passes out of thecavity 92 through the port 102 into the other tube 52.

It will be seen that the bands 36 and 38 embrace the contact shoes 44and are effective to press the shoes against the electrode 22. Moreover,the shoes are supported by the upper band 36. Each shoe has an outwardlyprojecting flange 118 at its upper end. The lower side of the flange 118engages the upper edge of the band 36 so that the band 36 prevents eachcontact shoe from moving downwardly relative to the electrode head. Eachshoe is retained against upward movement by a clamping plate 120 whichis secured to the shoe by a bolt 122. A tapped opening 124 is formed inthe outer side of each shoe to receive the bolt 122. It will be seenthat the clamping plate 120 has a shoulder 126 which engages the loweredge of the band 36 and prevents the shoe from moving upwardly relativeto the band. The clamping plate 120 also has a reduced end portion 128which overlaps the band 36 and securely clamps the outside of the shoeagainst the inside of the band.

The plate or inner member 88 of each contact shoe 44 is preferablywelded to the casting or outer member 86. The weld extends around allfour edges of the plate 88 and is clearly shown at 130 in FIG. 6. Asshown, the weld 130 is in the form of a V-shaped bead of metal which isflush with the surface of the contact shoe.

As already indicated, the contact shoes 44 are preferably made of amaterial such as copper which is highly conductive to both electricityand heat. However, the body 24 of the electrode head 20 does not have toconduct electrical current and may be made of a material such asstainless steel which is extremely strong and resistant to corrosion.The bands 36 and 38 may also be made of stainless steel or similarmaterial.

By means of bolts 132 or otherwise, the backplate 28 may be secured to amounting plate 134 on the outer end of the supporting arm 26. Holes 134'are formed in the backplate to receive the bolts.

It has been found that most of the wear, resulting from normal use ofthe electrode head, is concentrated at the contact shoes 44.Occasionally, the contact shoes may need to be repaired or replaced.With the construction of the present invention, each of the contactshoes 44 may easily be removed from the electrode head so that a newshoe may be installed. The shoes may be changed in a short time, so thatthe interruption in the operation of the electric furnace is minimized.Each shoe may be removed by loosening the main clamp 48, disconnectingthe tubes 50' and 52 from the shoe, and removing the clamping bolt 122,whereupon the shoe may be slid upwardly and removed from the bands 36and 38. The tubes 50 and 52 are disconnected by removing the bolts 114from the clamping plates 108. The bus bar clamp 54 may be loosened topermit the tubes 50 and 52 to be moved out of the way of the shoe, sothat it may be slid upwardly out of the electrode head 20. Thus, a wornshoe may be removed and replaced with a new shoe in a very short time.The worm shoe may then be repaired or rebuilt for additional service inthe future. Normally, the stainless steel body 24 and bands 36 and 38will last indefinitely and do not need to be repaired or replaced.

It will be evident that the electrode head of the present invention isefiicient and highly servicable. Moreover, it is economical and may berepaired very easily and quickly. Thus, the electrode head provides verylow operating and maintenance expenses.

Various other modifications, alternative constructions and equivalentsmay be employed without departing from the true spirit and scope of theinvention, as exemplified in the foregoing description and defined inthe following claims.

I claim:

1. In an electrode head for use with cylindrical electric furnaceelectrodes or the like,

the combination comprising a body adapted to be positioned opposite oneside portion of the electrode,

said body comprising a backplate and a pair of side members projectingtherefrom,

a pair of curved bands extending between said side members and adaptedto extend around the electrode,

a pair of contact shoes mounted on said bands and adapted to engage theelectrode to carry electrical current to the electrode,

means securing each contact shoe to at least one of the bands,

a clamping device engageable with the electrode between said sidemembers on said body for clamping said contact shoes against theelectrode,

a pair of tubes extending to each of said shoes for carrying electricalcurrent to the shoes and also for conducting cooling water to and fromthe shoes,

and means for disengageably connecting said tubes to said shoes,

each of said shoes comprising a curved casting and a curved plate weldedto said casting,

said casting and said plate having passages for carrying cooling watertherebetween.

2. In an electrode head for use with cylindrical electric furnaceelectrodes or the like,

the combination comprising a body adapted to be positioned opposite oneside portion of the electrode,

said body comprising a back member and a pair of side members projectingtherefrom,

said side members being formed with passages for the circulation of acooling medium,

a pair of curved bands extending between said side members and adaptedto extend around the electrode,

a pair of contact shoes mounted against the inside of said bands andadapted to engage the electrode to carry electrical current to theelectrode,

each shoe having an outwardly projecting member resting upon the upperedge of one of said bands,

a clamp forremovably securing each shoe to one of said bands,

a clamping device engageable with the electrode between said sidemembers on said body for clamping said contact shoes against theelectrode,

each shoe comprising curved inner and outer members welded together,

one of said members having channels therein forming passages betweensaid members for the circulation of a cooling medium,

a pair of tubes extending to each of said shoes for carrying electricalcurrent to the shoes and also for conducting the cooling medium to andfrom the shoes,

and means for removably connecting said shoes to the correspondingtubes.

3. In an electrode head for use with cylindrical electric furnaceelectrodes or the like,

the combination comprising a body adapted to be positioned opposite oneside portion of the electrode,

said body comprising a back member and a pair of side members projectingtherefrom,

said body being formed with passages for the circulation of a coolingmedium,

a plurality of curved bands extending between said side members andadapted to extend around the electrode,

a plurality of contact shoes mounted against the inside of said 'bandsand adapted to engage the electrode to carry electrical current to theelectrode,

each shoe having an outwardly projecting member resting upon the upperedge of one of said hands,

a clamp for removably securing each shoe to at least one of said bands,

a clamping device engageable with the electrode between said sidemembers on said body for clamping said contact shoes against theelectrode,

each shoe having passages therein for the circulation of a coolingmedium,

a plurality of tubes extending to each of said shoes for carryingelectrical current to the shoes and also for conducting the coolingmedium to and from the shoes,

and means for removably connecting said shoes to the correspondingtubes.

4. The combination of claim 3, in which each clamp engages both of saidbands and is connected to the corresponding shoe between said bands.

5. In an electrode head for use with cylindrical electric furnaceelectrodes or the like,

the combination comprising a body adapted to be positioned opposite oneside portion of the electrode,

said body comprising a back member and a pair of side members projectingtherefrom,

said body being formed with passages for the circulation of a coolingmedium,

a plurality of curved bands extending between said side members andadapted to extend around the electrode,

a plurality of contact shoes mounted against the inside of said bandsand adapted to engage the electrode to carry electrode current to theelectrode,

each shoe having an outwardly projecting member resting upon the upperedge of one of said bands,

means for removably securing each shoe to at least one of said hands,

a clamping device engageable with the electrode between said sidemembers on said body for clamping said contact shoes against theelectrode,

each shoe having passages therein for the circulation of a coolingmedium,

a plurality of tubes extending to each of said shoes for carryingelectrical current to the shoes and also for conducting the coolingmedium to and from the shoes,

and means for removably connecting said shoes to the correspondingtubes.

References Cited UNITED STATES PATENTS 2,475,209 7/1949 Tucker 219-1202,716,145 8/ 1955 Cartoux 13-46 2,997,511 8/1961 Turner 13--15 FOREIGNPATENTS 122,034 1/ 1919 Great Britain.

JOSEPH V. TRUHE, Primary Examiner.

1. IN AN ELECTRODE HEAD FOR USE WITH CYLINDRICAL ELECTRIC FURNACEELECTRODES OR THE LIKE, THE COMBINATION COMPRISING A BODY ADAPTED TO BEPOSITIONED OPPOSITE ON SIDE PORTION OF THE ELECTRODE, SAID BODYCOMPRISING A BACKPLATE AND A PAIR OF SIDE MEMBERS PROJECTING THEREFROM,A PAIR OF CURVED BANDS EXTENDING BETWEEN SAID SIDE MEMBERS AND ADAPTEDTO EXTEND AROUND THE ELECTRODE, A PAIR OF CONTACT SHOES MOUNTED ON SAIDBANDS AND ADAPTED TO ENGAGE THE ELECTRODE TO CARRY ELECTRICAL CURRENT TOTHE ELECTRODE, MEANS SECURING EACH CONTACT SHOE TO AT LEAST ONE OF THEBANDS, A CLAMPING DEVICE ENGAGEABLE WITH THE ELECTRODE BETWEEN SAID SIDEMEMBERS ON SAID BODY FOR CLAMPING SAID CONTACT SHOES AGAINST THEELECTRODE, A PAIR OF TUBES EXTENDING TO EACH OF SAID SHOES FOR CARRYINGELECTRICAL CURRENT TO THE SHOES AND ALSO FOR CONDUCTING COOLING WATER TOAND FROM THE SHOES, AND MEANS FOR DISENGAGEABLY CONNECTING SAID TUBES TOSAID SHOES, EACH OF SAID SHOES COMPRISING A CURVED CASTING AND A CURVEDPLATE WELDED TO SAID CASTING, SAID CASTING AND SAID PLATE HAVINGPASSAGES FOR CARRYING COOLING WATER THEREBETWEEN.